The present invention relates to an improvement of the Tamper Resistant Bait Cover (U.S. Pat. No. 5,927,000 to Edgar S. Bordes, Jr.). Accordingly, applicant incorporates by reference the section of U.S. Pat. No. 5,927,000 entitled xe2x80x9cBackground of the Invention,xe2x80x9d including the description therein of the field of the invention, the related art, and the objects of the invention. Applicant also incorporates the section entitled xe2x80x9cSummary of the Inventionxe2x80x9d and the drawings of U.S. Pat. No. 5,927,000.
Additional art related to the field of this invention includes U.S. Pat. No. 6,079,150 to Setikeas et al., which describes an insect-control system and method in the same general field as applicant""s U.S. Pat. No. 5,927,000.
The termite bait cover assembly disclosed in Pat. No. 5,927,000 requires the removal of the termite bait cover to detect the presence or absence of the target insect. Removal of the termite bait cover disturbs the feeding process of termites and tends to drive the termites away from the baiting system.
It is an object of this invention to allow a termite bait station to be evaluated for presence or absence of termites and termite activity without removing the bait cover.
Apertures in the bottom plate or top plate of the termite bait cover allow termite activity to be detected by conventional and future technologies. Preferably, the top plate has apertures, the apertures tapering from the bottom surface of the top plate to smaller openings on the top surface of the top plate. Small raised ridges form dimples and preferably surround the small openings on the top surface of the top plate. The dimples reduce or prevent moisture and light intrusion and enhance the effectiveness of the termite baiting system. Because termite bait assemblies frequently are installed in sidewalks or streets, the dimples may be made slip resistant.
Non-invasive termite detection methodologies include detecting methane and carbon dioxide gases produced by termite activity. These gases can be detected by conventional technology, such as by a device that produces a color change or a detectable signal. Several other detection technologies require either invasive detection or non-invasive access through the bait cover. In addition to producing methane and carbon dioxide, feeding termites change the moisture content of the bait. Feeding activity can also trigger a detectable transmission or color changes that could be detected through the cover assembly and that indicate the presence of active termites. The bait cover according to the current invention can accommodate all these technologies. An additional object of the present invention is to enable or enhance transmission of signals through the bait cover and to provide physical access to the bait station without removing the bait cover.
The system according to the present invention permits diagnosing and monitoring termite activity without removing the termite bait cover. Openings in the top and bottom of the bait cover enhance and expedite the detection process.
Some detection equipment is operable through a thin layer of material but not through the full thickness of the top plate. Hence another object of this invention is to provide a top plate having an area of decreased plate thickness. Preferably, the top surface of the top plate will remain as flat as possible, with the area of decreased thickness being created by the removal of material from the bottom surface of the top plate.
Some detection methods may operate through material other than the material from which the top plate is constructed. For example, where the top plate is made primarily of metal, plastic or other nonmetallic materials can allow detection of light, heat, or other emissions that are not detectable through a solid metallic top plate. The same principle holds true of top plates made of nonmetallic materials, such as plastics. Accordingly it is another object of this invention to provide a top plate having one or more areas comprising a material that effectively passes a detection signal.
Some detection methods may operate only through an aperturexe2x80x94for example, inserting fiber-optic cameras for visual inspection of the termite bait. Thus, a further an object of this invention is to provide a top cover having apertures that may be left open or that may be covered or plugged by a material that allows detection without removal of the cover plate.
Removal of the top cover assembly disclosed in U.S. Pat. No. 5,927,000 is accomplished by loosening a bolt in the cover assembly. This removal method can be time-consuming, especially when several bait stations require servicing. Hence, a further object of this invention is to provide a termite bait cover that may be removed and reinstalled quickly, using quick-removal pry tool.
These and other objects of this invention are met by providing apertures through the top and/or bottom plates of a termite bait cover.
Preferably, the top surface of the top plate has detection apertures that taper from a larger cross sectional area at the bottom surface of the top plate to a smaller cross sectional area at a dimple at the top surface of the top plate. The tapering of the apertures in the top plate minimizes the entry of moisture and light if the apertures are left open. Preferably, plugs can be placed in the apertures to exclude light and moisture, said plugs being either removable or constructed of materials that allow the transmission of sound waves, radio waves, light, infared radiation, or other signals correlated with any physical change detected by conventional or future termite detection technologies, thus allowing termite monitoring while minimizing disturbance of termite feeding activity. A plug may be an item shaped from solid material manufactured before use, such as a conventional rubber test-tube stopper. A plug also may be a mass of a self-curing material such as caulk, silicone, rubber, or other material that may be applied to an aperture in uncured form and allowed to cure, thus sealing the aperture.
An improved bottom plate may be used alone in conjunction with the improved top plate. Use of the bottom plate of the present invention along with the top plate of U.S. Pat. No. 5,927,000 may provide a sufficient increase in detection that the top plate of the present invention need not be employed to achieve effective monitoring.
In another embodiment of the invention, a cover assembly has a top having a top disc portion and a cylinder portion axially disposed downward therefrom, the cylinder portion having at least one retaining ridge encircling the cylinder portion and disposed upon the exterior surface thereof, and the cover assembly also having a bottom cup in the shape of a tapered cylinder having a bottom covering, said bottom cup being matable within the cylinder portion to expand the retaining ridge, and said bottom cup having an exterior diameter that tapers inward from the bottom of the bottom cup to the top thereof, said cover assembly being placed in the opening to seal the opening.
The retaining ridge is adjusted by inserting the bottom cup into the top until the desired amount of circumference expansion of the retaining ridge has occurred by actuating a threaded bolt inserted through the top plate assembly and threaded into the bottom assembly, thus pulling the bottom cup into the top and pushing the retaining ridge tightly against the walls of the termite bait opening when the bolt is tightened.
Preferably, the threaded bolt has a flat head, is countersunk within the top disc of the top and has two depressions in the head to accept the tip of a spanner or snake-eye screwdriver. Alternatively, some other tamper-resistant means for turning the bolt head, or even an ordinary screwdriver, can be used to tighten or loosen the thread bolt. When the top plate assembly and the bottom plate assembly are pulled together tightly, the bolt may have to be loosened to allow a removal tool to pry the tension adjustable bait cover out of the hole.
In another embodiment, the top assembly has at least one row of teeth disposed axially along the interior surface thereof, and the bottom cup has at least one row of teeth disposed axially along the exterior surface thereof, said teeth on said top and said teeth on said bottom cup being interlockable so as to prevent relative axial motion between said top and said bottom cup.
Typical cover assemblies having at least one retaining ridge and a top and a bottom cup interlocking teeth range between one-half inch and six inches in diameter. Typical cover assemblies having at least one retaining ridge and a top and a bottom cup joined by a bolt range between from two inches to twelve inches in diameter.
The non-axially-aligned apertures utilized in the current invention must be placed so that detection is not compromised. For some detection methods, the rubber gasket or portions of other components used with the current invention would prevent termite monitoring if the gasket or component appeared in the sight line between the non-axially-aligned aperture in the top plate and the termite bait. Other detection methods are not affected by the presence of the rubber gasket or other component portion in the sight line.